Process of making wrenches



April 1929- A. o. BRUNGARDT 1,711,083

April 30, 1929 A. o. BRUNGARDT 1,711,083

PROCESS OF MAKING WRENCHES Filed Feb. 20, 192 2 Sheets-Sheet 2 i 8 I1230 I3 I jiffy.

Patented Apr. 30, 1929.

UNITED STATES ALPHONSE 0. BBUNGABD T, OF SGITUATE, MASSACHUSETTS.

PROCESS OI MAKING WRENCHES.

Application filed February20, 1828. Serial No. 255,612.

This invention relates to a process of making wrenches, such, forexample, as plpe wrenches sometimes known as Stillsons and monkeywrenches, and more particularly to the formation of the bar or handleand frame or housing of wrenches intended for particularly hard serviceand therefore requiring exceptional strength.

An object of the invention is to provide a process by which the wrenchbar or handie and the frame or housing may be formed integral byforging, and by which the Jaw channel and nut window can be formed inthe frame or housing by successive operations.

It is common practice to form the bar or handle and frame or housing ofa wrench in one piece by castin Such wrenches have only the strength 0cast material which requires that the wrench be made in larger sectionsto equal the strength of forged wrenches. Consequently, cast wrenches inorder that they may approach the strength of forged wrenches, areheavier and unwieldy in use. Cast wrenches require steel bits or jaws,since teeth of sufficient strength and hardness cannot be made from castmaterial. Attempts have also been made to form the blanks comprising thehandle or bar and integral frame or housing-b forging, after which thejaw channel has een made by drilling and broaching the frame or housing.The drilling and broaching operations are very expensive and make thecost of the wrenches prohibitive.

With In process the wrench handle or bar and t e frame or housingthereof are formed integral b forging, and the jaw channel is provide inthe frame or housing by a forging operation known as piercing. The nutwindow which may be partially sunk in previous operations is completedby punching. Thus the bar or handle and frame or housing may'be formedofhigh carbon or alloy steel. Such steels have sufficient strength towithstand the severest sort of service. Such steels'also lend themselvesto heat treatments so that teeth can be cut in the bar or handle,eliminating the necessity of providing separate bits or jaws.

The process 'hereindescribed permits the manufacture, of the bars andframes for different types of wrenches, such, for example, as pipewrenches of the Stillson type having a tapered jaw channel, and themonkey wrench type with a jaw channel having parallel sides. y

The invention will be more fully understood from the followingdescription when taken in connection with the accompanying drawings andthe novel features thereof will be pointed out and clearly defined inthe claims'at the close of this specification.

In said drawings:

Fig. 1 is a perspective view of a forged bar or handle and integralframe or housing of a pipe wrench of the Stillson type formed inaccordance with my invention.

Fig. 2 shows the first step of my for 'ng process, by which theconstruction of Fig 1 is produced.

Fig. 3 is afragmentary elevation of the wrench bar and frame after theoperation of piercing to provide the channel in the frame.

Fig. 4 is a plan view illustrating the step of piercing the frame toprovide the longitudinal channel.

Fig. 5 is a fragmentary perspective view of the wrench handle of thepreceding figures after the frame has been punched to form the window.

Fig. 6 is a fragmentary view, part1. in

section, illustrating the process of punc ing out the window. 7

1 Figs. 7 to 12, inclusive, are corresponding figures, illustrating thesame steps of my process when used to form the bar and frame of a monkeywrench.

a Before explaining in detail the resent in-,

vention, and the method or mode 0 operation embodied therein, it is tobe understood that i the invention is not limited in its a plication tothe detailso'f construction an ment of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being ractised or carried out in various ways. lso itis to be understood that the phraseology or terminology employed hereinis for the purpose of description and not of limitation, and it is notintended to limit the invention beyond the terms of the several claimshereto appended or the requirements of the prior art.

Referring now to the drawings, 10 desig nates as a whole the forging,comprising an integral bar or handle and frame orhousing of a Stillsontype wrench formed in accordarrangeance with the invention, the bar orhandle being shown at 11 and the integral frame or housing at 12. InFig. 2there is illustrated the first step of the process of forming thewrench bar and frame. In this figure portions of a drop or steam hammerpress are shown, there being a base 20 having a lower die member 21 anda reciprocating head 22 carrying a cooperating upper die member 23. Thewrench bar and frame is shown in place between the cooperating diemembers. During this first operation I sink the window of .the frame fora portion of its depth, as shown pierces the channel 14 in the frame,which is in general rectangular in cross section and tapered (Fig. 3)the channel being wider at the upper end of the frame than at the loweror heel portion thereof.

After the piercing op ration has been completed, the bar or han e istransferred to a punch press having a base 30 and a reciprocating punchhead 31 carrying a punch 32 corresponding in form to the outline of thedepression 13 which defines the window, and adapted to cooperate withthe opening 30 It will be noted that the base or die member 30 isprovided with a depression or recess 30* adapted to receive the ear orprojection 15 formed at one side of the depression 13 of the frame whenthe handle and. frame are placed in position thereupon as shown in Fig.

6; B providingthe recess 3O the frame may e accurately positioned tocause the depression 13 thereof to register with the opening 30. Thepunch 32 is then operated to punch out the metal between the depressions13 to form the window 16 (Fig. 5).

The window is preferably provided with opposed convex walls 16 whichserve as hearing surfaces for the jaw nut of a complete or assembledwrench of the Stillson type,

wherein the movable jaw is permitted to rock member used to pierce thechannel in the frame 120 has parallel sides, rather than a tapered punchas employed in making the Stillson.

In Fig. 8 portions of a drop or steam han1- mer press for forming thebar and frame of Fig. 7 are shown. The press comprises a baseor fixedmember 200, provided with a die member 210 and a reciprocating head 220carrying a cooperating die member 230: The bar and frame of the monkeywrench are formed in the same manner as in the case of the Stillsonwrench. During the first operation, namely, that illustrated in Fig. 8,the depressions 130 are formed in the frame, the outline of saiddepressions representing the outline of the window to be formedsubsequently in the frame.

After com leting the initial step of the process, the ar is removed fromthe press and transferred to a forging machine, where it is held in avertical position between gripping or holding dies, such, for example,as the dies 240 and 250, mounted upon a base or support 260 (Fig. 10).In this figure a punch 270, with parallel sides, is shown which isadapted to pierce the longitudinal channel 140 in the frame, thusproducing a channel having parallel sides, as best shown in Fig. 9.

After the piercing operation has been completed, the bar is removed fromthe press and transferred to a suitable punching apparatus (Fig. 12).This apparatus com prises preferably a base 300 provided with an opening300, and a guide rib or projection 300 of a shape adapted to conform tothe shape of and receive and support the frame portion120 of the bar.Thus it will be seen that the rib serves as centering means for theframe and that the depressions 130 therein will be caused to registerwith the opening 300". The ap aratus also includes a reciprocable punchead 310 carrying a punch 320 corresponding in shape to the depressions130, which, when the frame is in position, is lowered to punch out themetal etween said depressions and form the window 1 (Fig. 11). Thiswindow is preferabl rectangular.

I rom the foregoing it will be seen that I have provided a processwhereby the bar or handle and the frame or housing may be madeintegrally from carbon or alloy steel at a low production cost.

' I claim:

1. The hereindescrlbed process of making wrenches having a bar orhandle, and a frame or housihg forged integrally therewith, said frameor ousing having a channel and window interce ting one another, whichconsists in forging the bar and frame in a single operation and byseparate operations piercing a channel in said frame and punching outthe channel-intercepting window in the frame.

2. The hereindescribed process of making wrenches having a bar orhandle, and a frame or housing forged integrally therewith, said frameor housing having a channel and window interce ting one another, whichconsists 5 in forging t e bar and frame, and sinking a window'in said:frame a rtion of the frame depth in a single operation and by separateoperations piercing a channel in said frame, and punching out to thefull depth of the frame the channel-intercepting window 0 therein.

In testimony whereof I aifix my signature.

ALPHONSE o. BRUNGARDT.

